Indicates whether tag descriptions rather than tag names should be displayed in the pen legend for tags being plotted by pens.
If set to 0 (false), then tag names are displayed consistently in the first cell for each pen in the pen legend (default).
If set to 1 (true), then tag descriptions are displayed consistently in the first cell for each pen in the pen legend.
Note: Depending on the setting of the TrendLegendDesc variable, the first cell for each pen in the pen legend will display either the name or description of the tag whose data is being plotted by the pen, regardless of the setting of the Descriptions drop-down list. For example, if you've set the TrendLegendDesc variable to 1 (true), then whether the Descriptions drop-down list is set to Value/Time, Maximum, or another setting, the description for the tag is always displayed in the first cell for the pen in the pen legend
Default: TrendLegendDesc = 0